<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8" />
  <meta http-equiv="X-UA-Compatible" content="IE=edge" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <title>Document</title>
</head>

<body>
  <script>
    let hero = {
      name: '吕布',
      age: 22
    }

    function sum(a, b, c) {
      console.log(a, b, c);
      console.log(a + b + c);
      console.log(this);
    }

    sum(2, 4, 6);
    sum.call(hero, 2, 4, 6);
    sum.apply(hero, [2, 4, 6]);

    // apply() 作用
    //    1. 调用函数，修改 this 指向
    //    2. 参数必须是数组(伪数组),数组解构为函数的形参

    console.log('-----------------------');
    console.log(Math.max(11, 22, 12, 1));
    let arr = [11, 22, 12, 1];
    console.log(Math.max(arr));

    // 原函数要求传递多个 number 类型的参数，
    // 使用 apply() 之后,传递的参数是一个数组
    console.log(Math.max.apply(Math, arr));

  </script>
</body>

</html>